<?php
/**
 * Created by PhpStorm.
 * User: hlcc
 * Date: 2016/12/27
 * Time: 9:58
 */
// php性能测试

$a = array();

for($i=0;$i<500000;$i++){

    $a[$i] = $i;

}

foreach($a as $i)

{

    array_key_exists($i, $a);

}